An overload-resistant support rod and its preparation method, installation method and refrigerated infrared detector

Abstract

The present invention provides an overload-resistant support rod and a preparation method, an installation method and a refrigerated infrared detector, which relate to the technical field of refrigerated infrared detectors, and include a plurality of rigid support sheets arranged in sequence, wherein the thickness direction of each rigid support sheet is parallel to the length direction of the support rod; both sides of each rigid support sheet are filled with elastic parts, the elastic parts are solidified by a polymer material solution, and the concentration of the polymer material solution forming the elastic parts in the middle area of ​​the support rod is higher than the concentration of the polymer material solution forming the elastic parts in the two end areas of the support rod. The beneficial effect is that the support rod is formed by staggered arrangement of rigid support sheets and elastic parts, so that the material, quantity and thickness of the rigid support sheets can be flexibly adjusted, as well as the type and concentration of the polymer material solution forming the elastic parts can be flexibly adjusted to meet the needs of different application scenarios, and the strength of the support rod is self-adaptive and overload-resistant.

Description

Technical Field

[0001] The present invention relates to the technical field of refrigerated infrared detectors, and in particular to an overload-resistant support rod and a preparation method and an installation method thereof, and a refrigerated infrared detector. Background Art

[0002] The cooling infrared detector Dewar assembly is the key to ensure the stable operation of the whole machine. The functional parts such as the substrate and cold screen are assembled at the movable end of the cold finger cylinder. However, due to the extremely thin (0.1-0.3mm) structural strength of the cold finger cylinder cannot meet the vibration and impact strength requirements, a support rod is required to support the movable end of the cold finger cylinder in actual use scenarios.

[0003] The heat transfer performance of the support rod is extremely important and directly affects the startup time of the infrared detector, especially when the infrared detector is used in the military field, it directly determines the response time of the missile or anti-missile system. The startup working rate of the infrared detector is directly related to the thermal conductivity of the support rod. Under the same cooling power, the lower the thermal conductivity of the support rod, the slower the heat transfer from the outside to the cold head, and the faster the chip can reach the operating temperature.

[0004] At present, support rods are usually made of ceramic materials with a thermal conductivity of 2-4W / (m·K). Although ceramic materials have low thermal conductivity, they are prone to brittle fracture during impact. In addition, after the support rod is bonded between the cold head and the ceramic lead ring, residual stress will be generated inside the ceramic support rod due to the shrinkage of the glue during curing; under impact conditions, the strength of the ceramic support rod will be lower than the design expectation. Summary of the invention

[0005] In view of the problems existing in the prior art, the present invention provides an overload-resistant support rod, comprising a plurality of rigid support sheets arranged in sequence, wherein the thickness direction of each rigid support sheet is parallel to the length direction of the support rod;

[0006] Both sides of each rigid support plate are filled with elastic parts, which are formed by solidifying a polymer material solution, and the concentration of the polymer material solution forming the elastic parts in the middle area of ​​the support rod is higher than the concentration of the polymer material solution forming the elastic parts in the two end areas of the support rod.

[0007] Preferably, the rigid support plate includes a ceramic plate and a titanium alloy plate, and the titanium alloy plate is located in the middle area of ​​the support rod, and the ceramic plate is located in the two end areas of the support rod.

[0008] Preferably, the polymer material solution is a hydrogel solution.

[0009] Preferably, some of the elastic members have cavities formed inside, and some of the cavities are injected with non-Newtonian fluid or elastic colloid.

[0010] Preferably, a spring is provided inside the elastic member, and the spring and the corresponding cavity are distributed in series or in parallel.

[0011] Preferably, an inverted cone structure is etched on both sides of each of the rigid support plates, and the inverted cone structure includes a plurality of grooves extending toward the interior of the rigid support plate along the thickness direction of the rigid support plate, and a protrusion is formed between two adjacent grooves. The cross-section of each of the grooves is trapezoidal and the upper base of the trapezoid serves as the opening of the groove.

[0012] The present invention also provides a method for preparing an overload-resistant support rod, which is used to prepare the above-mentioned support rod, and the preparation method comprises:

[0013] Step S1, configuring a mold including a plurality of slots, and inserting a plurality of rigid support sheets into each of the slots;

[0014] Step S2, pouring a polymer material solution into the mold, and scraping the surface of the polymer material solution to the same height as the rigid support sheet, and then curing the polymer material solution and demoulding;

[0015] Step S3, turning over the demoulding support member obtained by demoulding and inserting it into the mold, and then repeating step S2 to prepare the support rod.

[0016] Preferably, before executing step S2, it also includes etching both sides of each of the rigid support sheets to form an inverted cone structure, wherein the inverted cone structure includes a plurality of grooves extending toward the inside of the rigid support sheet along the thickness direction of the rigid support sheet, and a protrusion is formed between two adjacent grooves, and the cross-section of each of the grooves is trapezoidal and the upper base of the trapezoid serves as the opening of the groove.

[0017] The present invention also provides a method for installing an overload-resistant support rod, which is used to install the above-mentioned support rod into the infrared detector dewar, and the installation method comprises:

[0018] Step A1, bonding the two ends of the support rod to the outer shell of the Dewar and the cold head respectively, and then curing the bonding parts;

[0019] Step A2, heating the support rod to 80° C.-120° C. and maintaining the temperature for 20-60 minutes.

[0020] The present invention also provides a refrigerated infrared detector, comprising the above-mentioned support rod.

[0021] The above technical solution has the following advantages or beneficial effects:

[0022] 1) The support rod is formed by staggered arrangement of rigid support sheets and elastic parts, so that the material, quantity and thickness of the rigid support sheets can be flexibly adjusted, as well as the type and concentration of the polymer material solution forming the elastic parts can be flexibly adjusted to meet the needs of different application scenarios and achieve adaptive strength of the support rod;

[0023] 2) Use polymer material solution to form elastic parts, and use the viscoelastic properties of polymer materials to make the support rod stronger when it encounters high-intensity impact and vibration, so that the support rod has overload resistance and its strength can respond quickly to vibration impact;

[0024] 3) Since the concentrations of the polymer material solutions forming the elastic parts in different regions of the support rod are different, the strength in the middle of the support rod is high and the strength at both ends is low, so that the middle is not easy to break, and the two ends have good toughness and are not easy to fall off;

[0025] 4) The elastic part of the support rod of the present invention has much lower thermal conductivity and density than conventional ceramic support rods, which is beneficial to rapid cooling of the chip, rapid response of the detector, and lightweighting of the detector;

[0026] 5) The support rod of the present invention can release the stress caused by the shrinkage of the bonding glue by introducing polymer materials after being bonded to the Dewar by heating to 80-120°C, so that the material will not fail prematurely due to the internal stress inside the material during the subsequent vibration impact process. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 This is a schematic diagram of the internal structure of the support rod in a preferred embodiment of the present invention;

[0028] Figure 2 It is a schematic diagram of the structure of the cavity in a preferred embodiment of the present invention;

[0029] Figure 3 This is a schematic diagram of the structure of the nested cavity in a preferred embodiment of the present invention;

[0030] Figure 4a It is a schematic diagram of the spring and the cavity being distributed in series in a preferred embodiment of the present invention;

[0031] Figure 4b This is a schematic diagram of a preferred embodiment of the present invention, in which the spring and the cavity are distributed in parallel (one spring and two cavities are distributed at intervals);

[0032] Figure 4c This is a schematic diagram of a preferred embodiment of the present invention, in which springs and cavities are distributed in parallel (two springs and two cavities are distributed at intervals);

[0033] Figure 4dThis is a schematic diagram of a preferred embodiment of the present invention, in which springs and cavities are distributed in parallel (one spring and four cavities are distributed at intervals);

[0034] Figure 5 It is a schematic diagram of an inverted cone structure in a preferred embodiment of the present invention;

[0035] Figure 6 The figure is a flow chart of a method for preparing an overload-resistant support rod in a preferred embodiment of the present invention;

[0036] Figure 7 The figure is a schematic diagram of the process steps of a method for preparing an overload-resistant support rod in a preferred embodiment of the present invention;

[0037] Figure 8 The figure is a flow chart of a method for installing an overload-resistant support rod in a preferred embodiment of the present invention. DETAILED DESCRIPTION

[0038] The present invention is described in detail below in conjunction with the accompanying drawings and specific embodiments. The present invention is not limited to this embodiment, and other embodiments may also fall within the scope of the present invention as long as they conform to the gist of the present invention.

[0039] In a preferred embodiment of the present invention, based on the above problems existing in the prior art, an overload-resistant support rod is provided. Figure 1 As shown, it comprises a plurality of rigid support sheets 1 arranged in sequence, and the thickness direction of each rigid support sheet 1 is parallel to the length direction of the support rod;

[0040] Both sides of each rigid support plate 1 are filled with elastic parts 2, which are formed by solidifying a polymer material solution, and the concentration of the polymer material solution forming the elastic parts 2 in the middle area of ​​the support rod is higher than the concentration of the polymer material solution forming the elastic parts 2 in the two end areas of the support rod.

[0041] Specifically, in this embodiment, the support rod of the present invention is formed by staggered rigid structure and elastic structure as a whole, wherein the rigid structure is a rigid support sheet 1, and the rigid support sheet 1 includes a ceramic sheet 11 and a titanium alloy sheet 12. Considering that the middle part of the support rod is most prone to brittle fracture, the titanium alloy sheet 12 is located in the middle area of ​​the support rod, and the ceramic sheet 11 is located at the two end areas of the support rod. In other words, the use of the titanium alloy sheet 12 in the middle area makes the middle area of ​​the support rod have better toughness. It can be understood that the middle area and the two end areas here are relative concepts, and the size of the area is not limited. In the actual preparation process, the number of rigid support sheets 1 used and the size of the distribution area can be flexibly configured according to the use requirements, and the size of the rigid support sheet 1 can also be adjusted, such as doubling the thickness of the ceramic sheet 11, thereby adjusting the overall rigidity of the support rod.

[0042] Furthermore, elastic members 2 are filled on both sides of each rigid support sheet 1. The elastic members 2 are formed by curing a polymer solution, and after curing, the polymer solution can be directly connected to the rigid support sheet 1. Polymer solutions of various concentrations can be prepared according to demand, wherein the concentration of the polymer solution forming the elastic member 2 in the middle area of ​​the support rod is higher than the concentration of the polymer solution forming the elastic member 2 in the two end areas of the support rod, so that the strength of the support rod is high in the middle and low at the two ends, thereby achieving the middle not easy to break while the two ends have good toughness and are not easy to fall off.

[0043] In a preferred embodiment of the present invention, the concentration of the polymer material solution forming the elastic member 2 in the middle region of the support rod is 8%-20%, and the concentration of the polymer material solution forming the elastic member 2 in the end regions of the support rod is 5%-8%.

[0044] In a preferred embodiment of the present invention, the polymer material solution is a hydrogel solution.

[0045] Specifically, in this embodiment, the thermal conductivity of the elastic member 2 prepared by the hydrogel solution can be as low as 0.01-0.02W / (m·K), which is one order of magnitude lower than the thermal conductivity of the conventional ceramic support rod of 2-4W / (m·K), which is conducive to rapid cooling of the chip and rapid response of the detector. In addition, the density of the elastic member 2 prepared by the hydrogel solution can be as low as 0.0002g / cm 3 , compared to the density of conventional ceramic support rods 2.4-6g / cm 3 It is 4 orders of magnitude smaller, which is conducive to lightweighting of the detector.

[0046] In a preferred embodiment of the present invention, Figure 2 As shown, a cavity 21 is formed inside a portion of the elastic member 2 , and a non-Newtonian fluid or elastic colloid is injected into a portion of the cavity 21 .

[0047] Specifically, in this embodiment, after the elastic member 2 is cured, a laser can be used to carve a cavity 21 inside it. Taking the elastic member 2 formed by curing a gelatin solution as an example, considering that gelatin has good light transmittance, the support rod can be placed under a microscope, and the laser can be aimed at the gelatin area through the XYZ platform, and the Z-axis height can be adjusted so that the laser focus is aimed at the inside of the gelatin. The laser preferably uses an ultraviolet 355nm nanosecond laser, and the spot diameter after focusing is 10 microns. Three-dimensional space engraving is achieved through XYZ axis movement. The morphology of the engraved cavity is determined by the designed spot movement trajectory.

[0048] The size of the cavity 21 is preferably 10-100 microns. The cavity 21 formed after carving can maintain its original state, that is, the internal hollow state, or it can be injected with a non-Newtonian fluid or an elastic colloid to increase its strength. The cavity 21 can act as a damper and can quickly dissipate the kinetic energy caused by vibration. The elastic member 2 is preferably made of self-healing material, and a syringe can be used to puncture the cavity 21 and then inject a non-Newtonian fluid or an elastic colloid to achieve rapid healing of the cavity 21 after injection.

[0049] Furthermore, the specific adjustment of the overall strength of the support rod can be achieved by injecting the non-Newtonian fluid or elastic colloid into different pressures, the number of cavities 21 injected, and the positions. Preferably, the non-Newtonian fluid or elastic colloid can be injected into all the cavities 21 near the middle area of ​​the support rod, and the non-Newtonian fluid or elastic colloid can be injected into 70% of the cavities 21 at both ends of the support rod. It is understandable that different cavities 21 can also be injected with different types of non-Newtonian fluids or elastic colloids according to requirements.

[0050] The shape of the cavity 21 is not limited, and may include but is not limited to a positive direction, a triangle, and a ring. Figure 3 The nested cavities shown can preferably be formed by first carving out the inner cavity 211, and then scanning around the inner cavity with a laser focus to carve out an outer cavity 212 (wrapping the inner cavity 211), so that each layer of the cavity can be injected with different types of non-Newtonian fluids or elastic colloids, such as injecting the first non-Newtonian fluid or elastic colloid into the inner cavity through a microneedle, and then injecting the second non-Newtonian fluid or elastic colloid into the outer cavity. The nesting is not limited to two cavities, and can be multiple.

[0051] In a preferred embodiment of the present invention, a spring 22 is provided inside the elastic member 2, and the spring 22 and the corresponding cavity 21 are as follows: Figure 4a The cascade distribution shown or Figure 4b to Figure 4d The spring 22 can pass through multiple cavities 21 in sequence to form a parallel distribution. Figure 4a The spring 22 can also be spaced apart from the cavity 21 to form a series distribution structure as shown. Figures 4b to 4d In the parallel distribution structure, the following can be used: Figure 4b The manner in which one spring 22 and two cavities 21 are arranged at intervals may also be adopted, and the manner in which one spring 22 and one cavity ... Figure 4c The two springs 22 and the two cavities 21 are arranged in a spaced manner, wherein: Figure 4c The space occupied by the two springs 22 is Figure 4bThe space occupied by one spring 22 is the same, that is, two springs 22 distributed up and down are used to replace one spring 22, so that the force is more uniform. It can be understood that Figure 4c The size of the spring is smaller than Figure 4b In addition, the force can be more evenly distributed by adjusting the size of the cavity 21, such as Figure 4d As shown, a spring 22 and four cavities 21 are arranged at intervals, wherein: Figure 4d The space occupied by the four cavities 21 in Figure 4b The spaces occupied by the two cavities 21 are the same. Obviously, Figure 4d The cavity 21 in the embodiment has a smaller size. Figures 4a to 4d The number and distribution of the springs 22 and cavities 21 shown are for illustration only and are not intended to limit the present invention.

[0052] Specifically, if the internal strength of the elastic part 2 is insufficient, a spring 22 may be placed in the polymer material solution so that the spring 22 is fixed in the elastic part 2 after curing. The spring 22 is preferably a titanium alloy spring. The cavity 21 is combined with the spring 22 to play the role of elastic force support and damping dissipation, thereby adjusting the strength of the elastic part 2.

[0053] In a preferred embodiment of the present invention, both sides of each rigid support sheet 1 are etched with an inverted cone structure, such as Figure 5 As shown, the inverted cone structure includes a plurality of grooves 13 extending toward the inside of the rigid support plate 1 along the thickness direction of the rigid support plate 1, a protrusion 14 is formed between two adjacent grooves 13, and the cross-section of each groove 13 is trapezoidal and the upper base of the trapezoid serves as the opening of the groove 13.

[0054] Specifically, in this embodiment, the above-mentioned inverted cone structure can be obtained by laser peeling technology, and the size of the groove 13 is 50-200 microns, and the size here includes but is not limited to width, depth and length. By setting the inverted cone structure, it is possible to effectively prevent the rigid structure and the elastic structure from falling off during the process of the support rod being stressed.

[0055] The present invention also provides a method for preparing an overload-resistant support rod, which is used to prepare the above-mentioned support rod, such as Figure 6 As shown, the preparation method comprises:

[0056] Step S1, configuring a mold including a plurality of slots, and inserting a plurality of rigid support sheets into each slot respectively;

[0057] Step S2, pouring a polymer material solution into the mold, and scraping the surface of the polymer material solution to the same height as the rigid support sheet, and then curing the polymer material solution and demoulding;

[0058] Step S3, flipping the demoulding support member obtained by demoulding and inserting it into the mold, and then repeating step S2 to prepare a support rod.

[0059] Specifically, when the support rod needs to be prepared, the rigid support sheet 1 can be first inserted into the mold 3, such as Figure 7 As shown in (a), the polymer material solution is slowly poured into the mold 3. Figure 7 As shown in (b), a scraper is then used to flatten the surface of the polymer material solution until it is flush with the rigid support sheet, and then solidification is performed. The curing method here is not limited. If a hydrogel solution is used as the polymer material solution, curing can be achieved by chemical / physical cross-linking. If a gelatin solution is used as the polymer material solution, curing can be achieved by ultraviolet irradiation.

[0060] like Figure 7 As shown in (c), after curing and demoulding, the support rod is flipped over as shown in Figure 7 and inserted into the mold again, as shown in (d). Figure 7 As shown in (e), the polymer material solution is slowly poured into the mold 3 so that the remaining part of the rigid support sheet 1 is immersed, and then the surface of the polymer material solution is scraped flat with a scraper to the same height as the rigid support sheet, and finally the mold is demoulded after curing to obtain the following Figure 7 (f) shows the infrared detector support rod.

[0061] In a preferred embodiment of the present invention, before executing step S2, it also includes etching both sides of each rigid support sheet to form an inverted cone structure, the inverted cone structure includes a plurality of grooves extending toward the inside of the rigid support sheet along the thickness direction of the rigid support sheet, a protrusion is formed between two adjacent grooves, the cross-section of each groove is trapezoidal and the upper base of the trapezoid serves as the opening of the groove.

[0062] The present invention also provides a method for installing an overload-resistant support rod, which is used to install the above-mentioned support rod into the infrared detector dewar, such as Figure 8 As shown, the installation method includes:

[0063] Step A1, bonding the two ends of the support rod to the outer shell of the Dewar and the cold head respectively, and then curing the bonding parts;

[0064] Step A2, heating the support rod to 80°C-120°C and maintaining it for 20-60 minutes.

[0065] Specifically, in the present embodiment, the internal stress of the support rod can be released by heating the support rod, wherein the heating method may be a hot air gun or infrared laser defocused irradiation heating.

[0066] The present invention also provides a refrigerated infrared detector, comprising the above-mentioned support rod.

[0067] The above description is only a preferred embodiment of the present invention, and does not limit the implementation mode and protection scope of the present invention. For those skilled in the art, it should be aware that all solutions obtained by equivalent substitutions and obvious changes made using the contents of this specification and illustrations should be included in the protection scope of the present invention.

Claims

1. An overload-resistant support rod, characterized in that: It comprises a plurality of rigid support sheets arranged in sequence, wherein the thickness direction of each rigid support sheet is parallel to the length direction of the support rod; Both sides of each rigid support sheet are filled with elastic members, the elastic members are formed by solidifying a polymer material solution, and the concentration of the polymer material solution forming the elastic members in the middle area of ​​the support rod is higher than the concentration of the polymer material solution forming the elastic members in the two end areas of the support rod; Some of the elastic members have cavities formed inside, and some of the cavities are filled with non-Newtonian fluid or elastic colloid; A spring is arranged inside the elastic member, and the spring and the corresponding cavity are distributed in series or in parallel.

2. The support rod according to claim 1, characterized in that: The rigid support plate includes a ceramic plate and a titanium alloy plate, wherein the titanium alloy plate is located in the middle area of ​​the support rod, and the ceramic plate is located in the two end areas of the support rod.

3. The support rod according to claim 1, characterized in that: The polymer material solution is a hydrogel solution or a gelatin solution.

4. The support rod according to claim 1, characterized in that: An inverted cone structure is etched on both sides of each of the rigid support plates, and the inverted cone structure includes a plurality of grooves extending toward the inside of the rigid support plate along the thickness direction of the rigid support plate, and a protrusion is formed between two adjacent grooves. The cross-section of each of the grooves is trapezoidal and the upper base of the trapezoid serves as the opening of the groove.

5. A method for preparing an overload-resistant support rod, characterized in that: Used to prepare the support rod according to any one of claims 1 to 4, the preparation method comprising: Step S1, configuring a mold including a plurality of slots, and inserting a plurality of rigid support sheets into each of the slots; Step S2, pouring a polymer material solution into the mold, and scraping the surface of the polymer material solution to the same height as the rigid support sheet, and then curing the polymer material solution and demoulding; Step S3, turning over the demoulding support member obtained by demoulding and inserting it into the mold, and then repeating step S2 to prepare the support rod.

6. The preparation method according to claim 5, characterized in that: Before executing the step S2, it also includes etching both sides of each of the rigid support sheets to form an inverted cone structure, wherein the inverted cone structure includes a plurality of grooves extending toward the inside of the rigid support sheet along the thickness direction of the rigid support sheet, and a protrusion is formed between two adjacent grooves, and the cross-section of each of the grooves is trapezoidal and the upper base of the trapezoid serves as the opening of the groove.

7. A method for installing an overload-resistant support rod, characterized in that: Used to install the support rod according to any one of claims 1 to 4 into the infrared detector dewar, the installation method comprising: Step A1, bonding the two ends of the support rod to the outer shell of the Dewar and the cold head respectively, and then curing the bonding parts; Step A2, heating the support rod to 80° C.-120° C. and maintaining the temperature for 20-60 minutes.

8. A refrigerated infrared detector, characterized in that: Comprising a support rod as claimed in any one of claims 1 to 4.

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